Technical Field
The present disclosure relates to an endobronchial tool, and more particularly, to devices, systems, and methods for navigating an endobronchial tool to access tissue located outside a bronchus.
Description of Related Art
A common interventional procedure in the field of pulmonary medicine is bronchoscopy, in which a bronchoscope is inserted into the airways through the patient's nose or mouth. When treating malignancies of the lung, microwave ablation systems are often used in conjunction with an electromagnetic navigation (EMN) system. One such system is described in U.S. Pat. No. 6,188,355 and published PCT Application Nos. WO 00/10456 and WO 01/67035, the entire contents of which are hereby incorporated by reference. An EMN system typically includes a bronchoscope, a catheter assembly containing a location sensor at its steerable distal tip (e.g. locatable guide), an extended working channel that extends beyond the reach of the bronchoscope and becomes a pathway to the target site for subsequent diagnostic tools (e.g., biopsy tools, treatment catheters or laser, cryogenic, radio frequency, or microwave tissue treatment probes), and a computer system which provides the physician, or user, with navigational views of the lung. Once the bronchoscope is inserted into a patient's lungs, the locatable guide with the extended working channel is inserted into the bronchoscope. Using the navigation system and the steerable distal tip, the locatable guide and extended working channel is navigated to a target location. The locatable guide is then removed, leaving the extended working channel in place. Subsequent diagnostic tools can then be inserted into the extended working channel and directed to the target location.
However, in some cases, the target location or target tissue may be located outside the bronchial walls. In this situation, it is necessary to first insert the locatable guide through the extended working channel to guide the extended working channel towards the target tissue until the bronchial walls are reached. Once the locatable guide reaches the bronchial walls, the locatable guide must be removed from the extended working channel and a tool capable of piercing the bronchial walls is inserted into the extended working channel. The tool is used to pierce the airway wall and extend to the target lesion. The extended working channel is pushed over the tool and placed outside the airway wall. In order to confirm location of the extended working channel with respect to the lesion with the EMN system, the piercing tool is taken out of the extended working channel and the locatable guide is reinserted. Once the target tissue is reached, the locatable guide is removed and a biopsy tool or other instrument may be inserted through the extended working channel in order to act on the targeted tissue (e.g., perform a biopsy or ablation of the targeted tissue).
There is a need for a tool, or locatable guide, capable of penetrating the bronchus to access tissue located outside the bronchial walls while maintaining the ability to provide the physician with positional information on EMN, thereby minimizing the number of steps necessary to reach a target location.